From 672bb944311392e2415b39c0d63b1e1902905bcd Mon Sep 17 00:00:00 2001 From: Michal Srb Date: Thu, 20 Jul 2017 17:05:23 +0200 Subject: pcfGetProperties: Check string boundaries (CVE-2017-13722) Without the checks a malformed PCF file can cause the library to make atom from random heap memory that was behind the `strings` buffer. This may crash the process or leak information. Signed-off-by: Julien Cristau --- src/bitmap/pcfread.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'src/bitmap') diff --git a/src/bitmap/pcfread.c b/src/bitmap/pcfread.c index dab1c44..ae34c28 100644 --- a/src/bitmap/pcfread.c +++ b/src/bitmap/pcfread.c @@ -45,6 +45,7 @@ from The Open Group. #include #include +#include void pcfError(const char* message, ...) @@ -311,11 +312,19 @@ pcfGetProperties(FontInfoPtr pFontInfo, FontFilePtr file, if (IS_EOF(file)) goto Bail; position += string_size; for (i = 0; i < nprops; i++) { + if (props[i].name >= string_size) { + pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].name, string_size); + goto Bail; + } props[i].name = MakeAtom(strings + props[i].name, - strlen(strings + props[i].name), TRUE); + strnlen(strings + props[i].name, string_size - props[i].name), TRUE); if (isStringProp[i]) { + if (props[i].value >= string_size) { + pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].value, string_size); + goto Bail; + } props[i].value = MakeAtom(strings + props[i].value, - strlen(strings + props[i].value), TRUE); + strnlen(strings + props[i].value, string_size - props[i].value), TRUE); } } free(strings); -- cgit v1.2.3